The invention relates to a discharge installation to be used in a silo for bulk material in powdered of granular condition, comprising a column of collar plates disposed one above the other with a clearance and enclosing a central space forming a vertical discharge duct.
Such a discharge installation is known from German Offenlegungsschrift No. 1,914,600. In this case, the collar plates are provided with holes through which rods are fitted so as to form a column with said plates. This Auslegeschrift also discloses a discharge installation wherein the column is formed by helical collar plates.
It has become apparent, however, that for several types of bulk material to be stored in a silo the clearances between the collar plates get clogged nonetheless while there may occur arching of the material as well.